Coating compositions containing a titanyl fluorophthalocyanine pigment

Abstract

The invention provides a coating composition comprising a coating solution of a polymeric binder and an organic solvent having a gammac hydrogen bonding parameter value greater than 9.0, the coating solution having dispersed therein a titanyl fluorophthalocyanine pigment which has been acid-pasted or salt-milled to increase its photosensitivity and then has been brought into contact with an organic solvent having a gammac hydrogen bonding parameter value less than 8.0 to preserve its increased photosensitivity, prior to the pigment's being dispersed in the coating solution.

What is claimed is: 
     
       1. A coating composition comprising a coating solution of a polymeric binder and an organic solvent having a gamma c  hydrogen bonding parameter value greater than 9.0, the coating solution having dispersed therein a titanyl fluorophthalocyanine pigment which has been acid-pasted or salt-milled to increase its photosensitivity and then has been brought into contact with an organic solvent having a gamma c  hydrogen bonding parameter value less than 8.0 to preserve its increased photosensitivity, prior to the pigment's being dispersed in the coating solution. 
     
     
       2. The coating composition of claim 1, wherein the titanyl fluorophthalocyanine pigment has the structure ##STR2## wherein each of k, m, n, and q is independently an integer from 0 to 4, and at least one of k, m, n, and q is an integer from 1 to 4. 
     
     
       3. The coating composition of claim 2, wherein each of k, m, n, and q is 1. 
     
     
       4. The coating composition of claim 1, wherein the organic solvent having a gamma c  hydrogen bonding parameter value less than 8.0 has a gamma c  hydrogen bonding parameter value less than 7.0. 
     
     
       5. The coating composition of claim 1, wherein the organic solvent having a gamma c  hydrogen bonding parameter value less than 8.0 comprises dichloromethane, 1,1,2-trichloroethane, or methyl ethyl ketone. 
     
     
       6. The coating composition of claim 1, wherein the contact with an organic solvent having a gamma c  hydrogen bonding parameter value less than 8.0 comprises milling the pigment in such solvent for 3 days without external application of heat thereto. 
     
     
       7. The coating composition of claim 1, wherein the organic solvent having a gamma c  hydrogen bonding parameter value greater than 9.0 comprises tetrahydrofuran. 
     
     
       8. A coating composition comprising a coating solution of a polymeric binder and an organic solvent having a gamma c  hydrogen bonding parameter value greater than 9.0, the coating solution having dispersed therein a titanyl fluorophthalocyanine pigment which exhibits major x-ray diffractogram peaks, obtained with CuK alpha radiation, at Bragg angles (2θ±0.2) of 6.6, 7.1, 9.8, 11.6, 12.9, 14.9, 15.8, 18.2, 20.7, 23.2, 24.3, 27.0, 31.0, 32.5, 34.5, and 37.1. 
     
     
       9. The coating composition of claim 8, wherein the organic solvent having a gamma c  hydrogen bonding parameter value greater than 9.0 comprises tetrahydrofuran. 
     
     
       10. The coating composition of claim 8, wherein the titanyl fluorophthalocyanine pigment comprises titanyl tetrafluorophthalocyanine.